Methods of using compressible tubes for placing implants

ABSTRACT

Medical delivery devices include a needle and a flexible compressible impermeable tube attached to the needle. The compressible tube has an open interior channel. The device is adapted to releasably hold a length of a medical implant in the open interior channel of the tube. The medical implant can be slidably inserted into the interior channel of the tube and is loosely held by the tube.

RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalApplication Ser. No. 61/345,292, filed May 17, 2010, the contents ofwhich are hereby incorporated by reference as if recited in full herein.

FIELD OF THE INVENTION

The invention relates to medical constructs.

BACKGROUND OF THE INVENTION

It is believed that the linear organization of natural collagen fibersin tendons results in optimal stiffness and strength at low strainsunder tensile loads. However, this organization makes repairing tissuesuch as ruptured or lacerated tendons difficult. Current suturingtechniques to join split ends of tendons, while providing sufficientmechanical strength to prevent gapping, are often inadequate to carrynormal loads and may not ever allow the tendon to regain its originalmechanical properties or mobility. Immobilization protocols used torestore tendon congruity may result in scar formation at the repair siteand peripheral adhesions that can limit excursions. One or more similarissues may be associated with conventional ligament repair techniques.

When placing certain soft-tissue type implants, such, as for example,collagen fiber implants, the fibers can expand upon hydration, which canmake it difficult to place the implants in a desired orientation and/orposition in the body. Also, the collagen fibers may be somewhat fragileand subject to breakage when unprotected, such as when using hemostatclamps.

SUMMARY OF EMBODIMENTS OF THE INVENTION

Embodiments of the present invention are directed to medical deviceswith compressible tubes for placing medical constructs in the body.

Embodiments of the invention are directed to medical delivery devicesthat include a needle and a tube. The tube includes a first segment thatis attached to the needle and a second compressible and substantiallyimpermeable segment that increases in size relative to the first segmentand extends rearward of the needle. The second segment defines an openelongate interior channel adapted to loosely hold at least about 30% ofa length of a flexible medical implant therein.

The medical device can hold a flexible elongate medical implant with alength so that at least about 3 cm of the implant length is held in thecompressible second segment interior channel. The medical implant can beslidably insertable into the second segment interior channel and can beloosely held inside the tube interior channel spaced apart from theneedle during intrabody placement using the needle and tube.

In some embodiments, at least about 25%, typically at least about 30% ofthe length of the implant is held inside the compressible channel.

The flexible medical implant can be a partially hydrated or dry twistedor braided collagen fiber implant that is loosely held inside an outerwall of the tube second segment enclosing the interior channel.

The tube can have a forward end portion that resides in an interiorchamber of a rearward portion of the needle.

The tube can be swaged to the needle and has a smooth transition segmentfrom the needle to the tube to inhibit snagging when inserted throughsoft tissue during surgical use.

The tube can be attached to a drilled end needle.

The needle can have a length and the first segment of the compressibletubing can extend snugly against a portion of the needle, (e.g., 1 cm ormore, typically at least about 30% of the length of the needle). Thedevice can further include an elongate flexible braided or twistedcollagen fiber implant with at least about 3 cm of its length heldloosely in a substantially straight arrangement inside the secondsegment of the compressible tube.

The needle can be shank-less and have a constant diameter outer wallupstream from a tip portion thereof. An inner wall of the first segmentof the tube can be affixed to the outer wall of the needle. The devicecan further include a dry or partially hydrated collagen fiber implanthaving a length that swells (increases fiber diameter or size when inthe body), and the tube second segment can have a length that issufficient to encase at least about 30% of the implant held therein.

The tube can be formed of heat-shrink tubing that is heated to shrink toconform and affix to at least about 1 cm (in some embodiments 30%) of anouter wall of the needle.

The medical implant can be a tendon or ligament repair implant having asuture with at least 3 cm of its length being held in the second segmentof tube.

The medical implant held in the second segment of the tube can be alength of substantially or entirely dry or partially hydratedbiocompatible collagen fibers twisted or braided together that swellwhen exposed to a local fluidic environment in situ.

The medical implant held in the second segment of the tube can include aplurality of long fibers derived from soluble collagen that are in a dryor partially hydrated state and arranged as parallel long fibers thatare twisted and/or woven or braided together.

The fibers can include NDGA-polymerized collagen fibers.

The fibers can have a cross-sectional size, on average when dry, ofbetween about 0.001 inches to about 0.2 inches (when dry, on average),wherein the implant has a number of strands of fibers that is betweenabout 2-100, and wherein the number of fibers per strand is betweenabout 2 to 1200.

The medical implant can be for a ligament or tendon repair.

The medical implant can be at least one of a suture or a cable that isconfigured to repair an acromioclavicular (AC) joint.

The tube can be configured so that compression of a portion of thesecond segment caused by contact with surrounding local structure duringimplantation into soft tissue temporarily compresses the tube to tightlyhold the implant therein.

Other embodiments are directed to medical kits for a ligament or tendonrepair. The kits include a delivery device having a flexiblecompressible substantially impermeable tube with an open interiorattached to a needle having increased structural rigidity relative tothe flexible tube; and a length of tendon or ligament repair orreplacement material comprising dry or partially hydrated syntheticcollagen fibers releasably held in the open interior of the tube orprovided as a separate component for insertion into the open interiorchannel.

The repair or replacement material can be a twisted or braided constructof a plurality of collagen fibers. The delivery device and repair orreplacement material are held in at least one sterile package.

Still other embodiments are directed to methods of placing a medicalconstruct in the body of a subject. The methods include: (a) providing asurgical delivery device comprising a needle attached to a compressibletube with an open interior channel, the compressible tube surrounding anelongate medical construct having a body with a length, wherein at leastabout 3 cm of the construct body length is held in the open interiorchannel of the tube, wherein the construct body swells when exposed toliquid in the body of a subject; (b) pulling the needle and tube throughlocal intrabody structure; (c) compressing the tube and the medicalconstruct in response to pressure applied from contact with localstructure during the pulling step, thereby also pulling the portion ofthe medical construct held in the tube through the local structure; then(d) separating the medical construct from the tube after the compressingstep by continuing to pull the tube after the tube has exited the localstructure so that the medical construct is loosely held in the tube,thereby removing the tube from the medical construct and placing themedical implant in the body.

The medical construct can include dry or partially hydrated fibers whenheld inside the tube that swell when hydrated in the body.

The medical construct can include a plurality of strands ofbiocompatible collagen fibers having at least a portion that is braidedor twisted.

The method can further include inserting the needle in soft tissuebefore the pulling and compressing steps. The pulling can be carried outby pulling the needle and tube through the soft tissue. The compressingcan be carried out so that the tube and the medical construct arecompressed in response to pressure applied from contact with the softtissue during the pulling step thereby also pulling the portion of themedical construct held in the tube through the soft tissue. Theseparating step can be carried out by continuing to pull the tube afterthe tube has exited the soft tissue so that the medical construct isloosely held in the tube thereby removing the tube from the medicalconstruct and placing the medical implant in the body.

Yet other embodiments are directed to methods of assembling a medicaldelivery device with an implant for intrabody placement. The methodsinclude: (a) providing a needle attached to a compressible tube havingan open interior channel that extends a distance away from the needle;and (b) slidably inserting a medical implant comprising non-hydrated orpartially hydrated braided and/or twisted collagen fibers into the openinterior channel of the tube so that the implant is loosely held thereinfor intrabody placement using the needle and tube.

The implant can have a non-coated, non-tipped end, e.g., it may comprisea broomed end configuration.

The length of repair or replacement material can include a twisted orbraided construct of a plurality of collagen fibers. The delivery deviceand repair or replacement material can be held in at least one sterilepackage.

The medical construct can include fibers that swell when hydrated in thebody. The medical construct can include non-hydrated or partiallyhydrated strands of biocompatible collagen fibers having at least aportion that is braided or twisted.

It is noted that aspects of the invention described with respect to oneembodiment, may be incorporated in a different embodiment although notspecifically described relative thereto. That is, all embodiments and/orfeatures of any embodiment can be combined in any way and/orcombination. Applicant reserves the right to change any originally filedclaim or file any new claim accordingly, including the right to be ableto amend any originally filed claim to depend from and/or incorporateany feature of any other claim although not originally claimed in thatmanner. These and other objects and/or aspects of the present inventionare explained in detail in the specification set forth below.

Further features, advantages and details of the present invention willbe appreciated by those of ordinary skill in the art from a reading ofthe figures and the detailed description of the embodiments that follow,such description being merely illustrative of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side perspective view of a delivery device according toembodiments of the present invention.

FIG. 2A is a side perspective view of another delivery device accordingto embodiments of the present invention.

FIG. 2B is a side perspective view of the device shown in FIG. 2A beforeheat shrinking.

FIG. 2C is a top view of the delivery device shown in FIG. 2A shown inan exemplary use configuration according to some embodiments of thepresent invention.

FIGS. 3A-3C are a top view of the delivery device shown in FIG. 2A shownin an exemplary use configuration according to some embodiments of thepresent invention.

FIGS. 3D and 3E are schematic illustrations of a delivery device thatcan be used to define multiple entry and exit points in local tissueaccording to embodiments of the present invention and/or to secure twoadjacent pieces of tissue according to embodiments of the presentinvention.

FIG. 4A is a schematic illustration of a tendon repair procedureaccording to some embodiments of the present invention.

FIG. 4B is a schematic illustration of a tendon repair procedure similarto that shown in FIG. 4A but with an exemplary supplemental sutureconfiguration according to some embodiments of the present invention.

FIG. 4C shows an alternate embodiment of a collagen fiber ribbon implantthat can be placed using the delivery devices according to someembodiments of the present invention.

FIG. 5 is a schematic illustration of a medical kit according toembodiments of the present invention.

FIG. 6 is a flow chart of exemplary operations that can be used to carryout methods according to some embodiments of the present invention.

FIG. 7 is a side view of an exemplary delivery device adapted to hold asoft tissue implant according to embodiments of the present invention.

FIG. 8 is a side view of the delivery device enclosing a leading end ofthe implant shown in FIG. 7 according to embodiments of the presentinvention.

DETAILED DESCRIPTION

The present invention now is described more fully hereinafter withreference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

Like numbers refer to like elements throughout. In the figures, thethickness of certain lines, layers, components, elements or features maybe exaggerated for clarity. In the figures, broken lines illustrateoptional features or operations unless specified otherwise.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items. As used herein, phrases such as “between X and Y” and“between about X and Y” should be interpreted to include X and Y. Asused herein, phrases such as “between about X and Y” mean “between aboutX and about Y.” As used herein, phrases such as “from about X to Y” mean“from about X to about Y.”

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andrelevant art and should not be interpreted in an idealized or overlyformal sense unless expressly so defined herein. Well-known functions orconstructions may not be described in detail for brevity and/or clarity.

It will be understood that when an element is referred to as being “on”,“attached” to, “connected” to, “coupled” with, “contacting”, etc.,another element, it can be directly on, attached to, connected to,coupled with or contacting the other element or intervening elements mayalso be present. In contrast, when an element is referred to as being,for example, “directly on”, “directly attached” to, “directly connected”to, “directly coupled” with or “directly contacting” another element,there are no intervening elements present. It will also be appreciatedby those of skill in the art that references to a structure or featurethat is disposed “adjacent” another feature may have portions thatoverlap or underlie the adjacent feature.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, components, regions, layersand/or sections, these elements, components, regions, layers and/orsections should not be limited by these terms. These terms are only usedto distinguish one element, component, region, layer or section fromanother region, layer or section. Thus, a first element, component,region, layer or section discussed below could be termed a secondelement, component, region, layer or section without departing from theteachings of the present invention. The sequence of operations (orsteps) is not limited to the order presented in the claims or figuresunless specifically indicated otherwise.

The terms “implant,” “prosthesis” and “construct” are usedinterchangeably herein to designate an implantable medical productconfigured to repair or replace (at least a portion of) tissue,typically soft tissue, such as, for example, muscle, a natural tendon,ligament (e.g., ACL), AC joint, or other skin or tissue of a mammaliansubject (for veterinary or medical (human) applications). The term“implantable” means the device can be inserted, embedded, grafted orotherwise chronically attached or placed on or in a patient.

The term “impermeable” with respect to the delivery system tube meansthat the device is resistant to liquid diffusion so as to inhibit undueswelling (e.g., hydration) of any implant or construct material heldtherein during placement of the construct in a mammalian body.

The term “needle” refers to a substantially rigid device that has asharp leading end.

The term “loosely held” means that the medical implant material can beslidably inserted into the tube and resides in the tube in a useconfiguration with a low engagement force, e.g., the implant can beeasily separated from the tube by pulling the end of the material notheld by the tube or by pulling the needle end of the tube with a lowtensile force while the material extending from the other end of thetube is held with a clamp or frictional engagement with local structure.The medical implant is not in snug abutting contact with an outer wallof the compressible tube.

The term “collagen fibers” refers to natural and syntheticcollagen-derived fiber materials. Collagen “microfibrils,” “fibrils,”and “natural fibers” refer to naturally-occurring structures found in atendon. Microfibrils are about 3.5 to 50 nm in diameter. Fibrils areabout 50 nm to 50 μm in diameter. Natural fibers are above 50 μm indiameter. A “synthetic fiber” refers to any fiber-like material that hasbeen formed and/or chemically or physically created or altered from itsnaturally-occurring state. For example, an extruded fiber of fibrilsformed from a digested tendon is a synthetic fiber, but a tendon fibernewly harvested from a mammal is a natural fiber. Of course, syntheticcollagen fibers can include non-collagenous components, such asparticulates, hydroxyapatite and other mineral phases, or drugs thatfacilitate tissue growth. See, U.S. Pat. No. 6,821,530, herebyincorporated by reference herein. For example, the compositions cancontain carbon nano-tubes, zinc nano-wires, nano-crystalline diamond orother nano-scale particulates, and larger crystalline andnon-crystalline particulates such as calcium phosphate, calcium sulfate,and apatite minerals. For example, the fibers and/or constructs formedof the fibers can include compositions that contain therapeutic agentssuch as bisphosphonates, anti-inflammatory steroids, growth factors suchas basic fibroblast growth factor, tumor growth factor beta, bonemorphogenic proteins, platelet-derived growth factor, and insulin-likegrowth factors; chemotactic factors such fibronectin and hyaluronan; andextracellular matrix molecules such as aggrecan, biglycan, and decorin.In some embodiments, the fibers and/or constructs can contain cells,engineered cells, stem cells, and the like, as well as combinations ofthe above.

The term “flexible” means that the so-called member can be flexed orbent.

The terms “braided” and “woven” and derivatives thereof mean structuresthat are braided and/or (inter)woven, interlaced and/or interlocked inany manner, with a plurality, typically three or more, fibers or bundlesof fibers together, including manually or automatically woven, braided,knitted and/or knotted and combinations of these or other interlockingor interlaced constructions. The woven constructs may comprise aplurality of warp and weft fibers. The fibers are typically collagenderived fibers.

The term “twisted” and derivatives thereof mean to entwine two or morestrands of fibers, typically collagen derived fibers, into a singlestrand. The twisted configuration can be formed by serially turning thefibers/strands in a clockwise or counter clockwise direction tointroduce a series of turns extending along a lengthwise direction,including manually or automatically twisting the fibers and/or fiberbundles. The strands can have a single fiber or multiple fibers.

The construct, typically formed or comprising long (e.g., between about1 cm to about 1 m) synthetic collagen (derived from donor collagenfibrils) fibers, may have a substantially constant length, whether inthe dry or partially hydrated configuration or the fully hydratedconfiguration but typically swell upon exposure to hydration relative toa size at a dehydrated or partially hydrated state as held inside thecompressible tube during delivery.

The term “dry” or “dehydrated” means the construct fibers have amoisture content that is substantially less than the moisture amountthat is present when fully hydrated. The term “partially hydrated” meansthat the construct and/or fibers thereof have a moisture content that isless than about 50%, typically less than about 75% of the moisturecontent at full hydration, measured ex vivo after 24 hours in a salinebath at ambient conditions.

Referring now to the figures, FIG. 1 shows an example of a medicaldelivery device 10. The device 10 includes a needle 15 and a flexibletube 20. The tube 20 may be optically transmissive (e.g., translucent ortransparent) to allow a clinician to view the portion of the medicalimplant 50 held in the interior of the tube 20. The tube 20 may beimpermeable to inhibit swelling (e.g., hydration) of the implantmaterial during positioning of the implant 50 (FIG. 3A) in the bodybased on exposure to local conditions (body fluids) using the deliverydevice 10.

The needle 15 can have one or two open ends or closed ends. The needle15 may have an open or closed leading end with the leading end 15/beingsharp and relatively small for ease of insertion through localstructure, such as, for example, soft tissue. The needle 15 may have asolid body or may have a hollow body (e.g., have a cannulaconfiguration). The needle can be a drilled-end needle or fenestratedneedle. The needle 15 can have an open proximal end 15 e. The needle 15may be formed from hypodermic tubing. The needle 15 may have a circular(cross-section) or other geometric configuration. The needle 15 may be a12 gauge needle (e.g., have a forward end of about 0.08 inches or less,such as between about 0.04 to about 0.08 inches) and the tube 20 may beslightly larger. The needle 15 can have a constant size or may taperfrom a forward end to a distal and/or medial section. The needle 15 istypically shank-less, e.g., it does not require a smaller neck facingthe implant in the tube 20, but may optionally have a shank. An exampleof needle with a shank that is snugly attached to a small tipped leadingedge of a suture is shown in U.S. Pat. No. 5,259,845, the contents ofwhich are hereby incorporated by reference as if recited in full herein.

The tube 20 can be attached to the needle 15 in any suitable manner. Inthe embodiment shown in FIG. 1, the tube 20 can be attached to theneedle 15 by inserting a forward or leading edge portion of the tube 20f into an interior 15 i of the (hollow or open end) needle 15. The twocomponents 15, 20 can also be swaged together, similar to a sutureneedle. However, other attachment configurations may also be used, forexample, adhesive attachment, ultrasonic bonding, crimping, heat shrinkand the like. As shown, the attachment transition region “t” between theneedle 15 and the larger tube 20 can be relatively smooth to facilitateease of insertion (and anti-snagging) during use.

FIGS. 2A and 2B illustrate alternate embodiments of the delivery device10′. As shown, the device 10′ includes a tube 20 that can be attached toan exterior surface or wall of the needle 15 w. In some embodiments, thetube 20 can be heat-shrink tubing that can be heated to shrink againstand conformably attach to the outer wall of the needle 15 w. The tube 20can include a first segment 22 that snugly resides about the needle 15and a larger elongate second segment 23 that defines an open channel andhas a larger size that can loosely hold the implant for delivery and/orintrabody placement. Where the tube 20 is mounted to an exterior surfaceof the needle 15, the first segment 22 of the tube 20 can reside over atleast a major portion of a length of the needle 15. In some embodiments,the needle 15 can have a length that is between at least 10-50% of thelength of the second segment 23 of the tube extending rearward of theneedle 15.

FIG. 2B illustrates the tube 20 before heat shrinking and FIG. 2Aillustrates the tube 20 firmly attached to the needle 15 after heatshrinking. FIG. 2A illustrates that the tubing 20 can extend close to,e.g., adjacent, a forward/leading end of the needle 15 so that the tube20 overlies at least a major portion of the length of the needle 15,with the heat shrink portion 20 h typically residing over between about20% to about 95% of the length of the needle, and more typically betweenabout 30-70% of the length of the needle.

In other embodiments, the tube 2Q can be configured to reside over aminor portion of the length of the needle and/or or a smaller length orportion of the tube 20 overlying the needle 15 may be heat-shrinkattached to the needle 15, such as, for example, at least about 1 cm.

The needle 15 may have a length “L” (FIG. 2C) that is between about70-100% of the length of the second segment 23 of the tube 20 (FIGS. 7,8). In other embodiments, the needle 15 may have a shorter length thanthat shown, such as 30%, 20% or even 10% or less the length of thesecond segment 23. As before, the transition “t” between the end of theneedle 15 and the larger tube 20 can be relatively smooth (a gradualincrease in size). However, other larger, typically tapered, transitionscan be used.

The tube 20 can be configured to fit or accommodate the implant 50 andcan, in some embodiments, loosely and releasably hold the implant 50therein. As shown in FIG. 2C, the leading end of the implant 50 canreside a distance “D” spaced apart from the trailing end of the needle,so as to be in non-abutting (non-compressive contact) relationship withboth outer wall of the tube thereat and the end of the needle. The tube20 can, for example, have a diameter of between about 0.05 inches toabout 0.5 inches, typically between about 0.1 to about 0.2 inches, forcertain medical uses, such as, for example, soft tissue repairs,including tendon and/or ligament repairs. However, other dimensions andsizes may be used.

The tube 20 can have a length sufficient to define an open interiorchannel that can encase between about 20-100% of the implant 50 fordelivery in the body, typically between about 30-70% of the length ofthe implant, including, for example about a leading half of the implant.The implant 50 can be provided in any desired length, typically betweenabout 0.5 cm to about 50 cm, more typically between about 1 cm to 25 cm.In some embodiments, the implant 50 has a length between about 5 cm toabout 25 cm, including between about and about 10 cm to about 15 cm orbetween about 15 to 20 cm. The implant 50 may have a width between about0.05 to 8 cm, and is typically between about 1-3 cm. The implant 50 mayhave a thickness of between about 0.01 to about 30 mm, typically about1-10 mm. The at least one suture 250 can extend at least about 1 inchoff beyond each end of the ribbon body, typically between about 1-15inches. The suture(s) 150 (where used) can be shorter on one end thanthe other (not shown). The implant 50 can include integrated sutures 250that are woven into and extend over the entire length of the implant L₃and beyond (see, e.g., FIG. 4C).

A common tube 20 and/or needle 15 size can be used to place a pluralityof different size constructs because the implant 50 is typically looselyheld in the tube 20. For example, a 12 gauge needle (a diameter of about0.08 inches) with about a 0.0935 inch tube can be used to place a 108,216 and 432 collagen fiber braid of various corresponding sizes. A morecomplete description of woven and braided collagen fiber constructs andmethods of making same can be found in U.S. patent application Ser. No.11/964,745, the contents of which are hereby incorporated by referenceas if recited in full herein.

The tube 20 can be a thin polymeric material such as, for example, PTFEtubing. The term “thin” refers to tubing material that is between about0.01 to about 0.0015 inches thick and may be even thinner. However, thetube 20 can include other polymers and/or be formed in otherthicknesses. The tube 20 and/or needle 15 can be used with or without alubricous biocompatible coating for ease of insertion. The biocompatiblecoating may also include therapeutic agents, such as anti-inflammatoryand antibiotic materials. The term “polymer” refers to polymers,copolymers and derivatives and combinations thereof.

FIG. 3A illustrates the delivery device 10, 10′ being used to place aconstruct 50 in soft tissue, such as a tendon. As shown, the device 10,10′ holds the elongate construct 50. FIG. 3A also illustrates that theconstruct 50 may be a braided (mesh) fiber construct.

FIG. 3A illustrates that a portion of the construct 50 is held and/orresides in the tube 20 and a portion of the construct 50 trails/extendsoutside of and behind the tube 20. The device 10, 10′ can be used topull the construct 50 through the soft tissue 90 out of an opening 91formed by the needle 15. As the tube 20 passes through the localstructure 90, e.g., surrounding structure (e.g., surrounding tissue)applies a compressive force “Fc” to the body of the tube 20 therebyfirmly grasping the implant material 50 therein. After the tube 20 exitsthe local structure, e.g., soft tissue 90, the compressive forces Fc(e.g., pressure) on the tube 20 automatically abate, e.g., stop. Thedevice 10, 10′ and implant 50 can be easily disconnected when the tubeis pulled after it exits the local structure 90.

FIGS. 3A-3C illustrate a sequence of steps (steps 1-3) that can be usedto place the implant 50. FIGS. 3A-3C also illustrate that the implant 50can be a twisted implant 50 t or braided implant 50 b of fibers, suchas, for example, twisted or braided long (typically at least 2 incheslong) collagen fibers that are held in the tube 20 in a partially ortotally dehydrated state, and that, when placed in the body swell uponhydration. The implant 50 can be planar or tubular. For a more completedescription of suitable twisted collagen fibers and methods of makingsame, see, U.S. patent application Ser. No. 12/465,433, the contents ofwhich are hereby incorporated by reference as if recited in full herein.

Step 1 (see FIG. 3A) shows the device 10, 10′ with the tube 20compressed by local structure to grasp the implant 50 t. Step 2 (seeFIG. 3B) illustrates the tube 20 exiting the local structure (e.g., softtissue) via exit port 91 created by the needle 15 thereby removing thecompressive force that held the implant 50 t. Step 3 (see FIG. 3C) showsthat the device 10, 10′ can be easily separated from the implant 50 bypulling the device 10, 10′ which, without the compressive forces appliedby the surrounding tissue, allows the device 10, 10′ to be removed fromthe implant 50 t while the implant remains in the target tissue 90 witha portion extending through port 91.

FIGS. 3D-3E illustrate that the delivery device 10, 10′ can be used tomake multiple entries and exits from local tissue, such as in twoadjacent pieces of soft tissue 90 a, 90 b (e.g., created by a tornligament or tendon) before releasing the delivery device 10, 10′ fromthe implant material 50.

FIG. 3D illustrates that the delivery device 10, 10′ can be used topenetrate local tissue in multiple entry and exit positions (labeled aslocations “1”-“8”) and position the implant 50 to extend between the twopieces of local tissue 90 a, 90 b (such as a torn ligament or tendon)and be secured to both pieces. FIG. 3E illustrates an alternate exampleof entry and exit positions.

FIG. 4A illustrates an example of a tendon repair with the implantmaterial 50 in position based on the use of the delivery device 10, 10′.As shown, the implant 50 can include a fixation knot 51, such as a nailknot defined by loops of a suture (such as a six loop nail knot). Theknot 51 can be held in the tube 20 during delivery/implantation usingthe delivery device 10, 10′. FIG. 4B illustrates the implant 50 shown inFIG. 4A with a supplemental suture 150. The supplemental suture 150 canbe a #2 TiCron suture configured with Krackow stitches, such as about 6on each side of the tear 90 a, 90 b to help stabilize the implant 50 inposition and/or provide additional structural support at least during aninitial healing period post surgery. However, the delivery device 10,10′ can also be used to place other implants. As shown in FIG. 4C, thedelivery device may be configured to hold and deliver braided ribbons 50r with at least one integrated suture 250 that extends over the entirelength of the implant L₃ and out from each end a distance L₄. Theextension length L₄ can be between 1-500 mm or even greater, but istypically between about 20-400 mm. For additional description ofcollagen fiber ribbons with integrated sutures, see co-pending,co-assigned, U.S. Provisional Application Ser. No. 61/450,179, thecontents of which are hereby incorporated by reference as if recited infull herein.

Also, the construct 50 can optionally include, e.g., be coated,impregnated and/or amalgamated with, a gel or other material. Thecoating may be to promote fibroblasts, and/or comprise one or more of ananti-inflammatory agent, an antibiotic or other therapeutic agent. Theconstruct 50 can be absorbed, resorbed and/or biodegradable over time.In some embodiments, the constructs 50 can be configured to have similaror greater tensile strength, stiffness and dynamic flexibility ascorresponding natural tissue, e.g., natural ligament or tendon fibers.Embodiments of the invention may be particularly suitable foraugmenting, repairing or replacing tendons and ligaments.

In some embodiments, the fibers comprise collagen fibers formed in anysuitable manner to be acceptable as a biomedical implant/construct.

As noted above, in particular embodiments, the fibers can compriseNDGA-treated collagen. Suitable ways of forming NDGA-polymerized and/or—treated fibers are described in U.S. Pat. Nos. 6,565,960 and 6,821,530,the contents of which are hereby incorporated by reference as if recitedin full herein. Generally stated, bulk collagen can be solubilized bydigestion with a protease, then extruded into a synthetic fiber.Properly processed NDGA polymerized fibers are biocompatible. After thepolymerization process, the fibers can be washed in ethanol andphosphate buffered saline to remove cytotoxins due to leachable reactionproducts.

NDGA-treated collagen fibers are biocompatible and have desirablemechanical properties. For additional discussion of the NDGA polymerizedfibers, see, Thomas J. Koob, Biomimetic approaches to Tendon Repair,Comparative Biochemistry and Physiology Part A 133 (2002) 1171-1192.

In some embodiments, the collagen fibers may be high-strength. The term“high-strength” refers to fibers having an average tensile strength ofat least about 150 MPa, such as between about 180 MPa and 350 MPa, andtypically, for bovine-, porcine- or caprine-based “donor” collagen,between about 180 MPa and 280 MPa, such as between about 240-279 MPa(measured on average). The fibers may also have suitable stiffness andstrain yield. In general, the fibers can have a stiffness of at leastabout 200 MPa (e.g., at least about 300, 400, 500, or 600 MPa), and astrain at failure of less than about 20% (e.g., less than about 15 or10%).

In particular embodiments, the fibers may be formed with a relativelythin diameter, such as, for example about a 0.07 mm dry diameter (onaverage) and about a 0.09 mm wet diameter (on average) or a dry diameteron average of about 0.08 mm and a wet diameter on average of about 0.13mm. However, other sizes may be used.

To make the collagen fibers, preparatory donor collagen material can bepepsin-derived or solubilized collagen that is processed/purified. Thepurified collagen preparatory material is dialyzed a plurality of timesin a selected liquid for a desired period of time. The dialyzing istypically repeated three times. The dialyzing can be carried out againstdionized (DI) water in a volume ratio of between about 30:1 to about100:1, typically about 60:1, for between about 30-90 minutes, typicallyabout 40 minutes. The dialyzing can form a substantially clear gel ofcollagen fibrils indicating good organization (substantially parallelfibrils), where opacity indicates less organization. The organizationcan help improve tensile strength of subsequently cross-linked fibers.

The dialyzed collagen material can be incubated for a desired timebefore placing in a fiber-forming buffer. The dialyzed gel can becross-linked to provide collagen fibers for medical constructs. Thepolymerization (e.g., cross-linking) can be carried out using NDGA orother suitable cross-linking agent and the resultant collagen fibers canbe relatively thin, such as, for example, about 0.08 mm dry diameter (onaverage).

The incubation may be for at least about 24 hours, typically 24-48hours, and may be at room temperature of between about 15-30° C.,typically about 25° C. The dialysis process can be used beforecross-linking for subsequent use with any suitable cross-linkingmaterials, such as, for example, to promote collagen organization, andthe process is not limited to NDGA, but may be useful with othermaterials, including, for example, glutaraldehyde. For additionaldiscussion of methods used to form high-strength NDGA treated collagenfibers, see, U.S. patent application Ser. No. 11/964,756, the contentsof which are hereby incorporated by reference as if recited in fullherein.

The implants 50 can include swellable collagen fibers that have across-sectional size, on average, when dry, of between about 0.001inches to about 0.2 inches. The implant can include a number of strandsof collagen-derived fibers such as between about 2-100, and the numberof fibers per strand can be between about 2 to 1200.

In some embodiments, the implant 50 may have between about 1-1000 yarns,typically between about 3-100 yarns some of which are weft and some ofwhich are warp yarns. The implant 50 can be configured to havesubstantially the same physical thickness and/or configuration as thereplaced or repaired tissue so as to not cause discomfort or physicalabnormalities in structure.

As desired, the body of the implant 50 can include a smooth outer sheaththat may be formed by a coating, gel or other material. In particularembodiments, the implant 50 can comprise polyglycolic acid, polylacticacid, or combinations of these or other substances.

FIG. 5 illustrates a medical kit 75 that includes the delivery device10, 10′ and optionally, at least one construct 50, in a sealed package88. The construct 50 may be held dehydrated or partially hydrated in thepackage 88 or in another separate package (not shown). The kit 75 mayinclude a temperature warning so that the construct 50 is not exposed tounduly hot temperatures that may degrade the implant. A temperaturesensor 80 may optionally be included on or in the package 88 of the kit75 to provide a visual or audible alert to a clinician as to anyexcessive or undue temperature exposure prior to implantation. Theconstruct 50 can be held in the tube 20 in the package 88. The construct50 can be inserted into the tube 20 of the device 10, 10′ by theclinician in situ. This may also allow the clinician to select thedesired construct 50 from constructs 50 in a range of sizes that may bepart of the package 88 or provided as separate content. The deliverydevice 10, 10′ can be a “universal” delivery device that is configuredto accommodate soft tissue implants in a range of sizes.

FIG. 6 is a flow diagram of exemplary operations that can be used tocarry out embodiments of the present invention. A flexible tube with anopen interior channel attached to a needle and having an elongatemedical construct having a length with a portion held in the openinterior channel is provided (block 100). The needle and tube are pulledthrough local structure (block 105). The tube and the medical constructare compressed in response to pressure applied from contact with localstructure during the pulling step, thereby also pulling the portion ofthe medical construct held in the tube through the local structure(block 110). The medical construct is then separated from the tube afterthe compressing step by continuing to pull the tube after the tube hasexited the local structure so that the medical construct is loosely heldin the tube, thereby removing the tube from the medical construct andplacing the medical implant in the body (block 115).

The local structure can optionally be soft tissue (block 107). Theconstruct can optionally be loosely held in the tube and temporarilycompressed by contact with the local structure (block 103).

Although described herein primarily with respect to collagen-derivedfiber implants, it is contemplated that the delivery devices 10, 10′ candeliver other types of implants.

The present invention is explained in greater detail in the followingnon-limiting Examples.

EXAMPLES

FIGS. 7 and 8 show a delivery device 10′ with the tube 20 as a heatshrink tube and with the medical construct 50 formed with braidedNDGA-collagen fibers. FIG. 7 illustrates that the heat shrink portion 20h extends over more than half of the length of the needle 15 and thatthe second segment of the tube 23 has a length that is between about60-100% that of the needle 15. As shown, the second segment 23 has alonger length L₂ than the length L₁ of the needle 15.

The foregoing is illustrative of the present invention and is not to beconstrued as limiting thereof. Although a few exemplary embodiments ofthis invention have been described, those skilled in the art willreadily appreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention as defined inthe claims. The invention is defined by the following claims, withequivalents of the claims to be included therein.

1. A method of placing a medical construct in the body of a subject,comprising: providing a surgical delivery device comprising a needleattached to a compressible tube with an open interior channel, thecompressible tube surrounding an elongate medical construct having abody with a length, wherein at least about 30% of the construct bodylength is held in the open interior channel of the tube, wherein theconstruct body swells when exposed to liquid in the body of a subject;pulling the needle and tube through local intrabody structure;compressing the tube and the medical construct in response to pressureapplied from contact with local structure during the pulling step,thereby also pulling the portion of the medical construct held in thetube through the local structure; then separating the medical constructfrom the tube after the compressing step by continuing to pull the tubeafter the tube has exited the local structure so that the medicalconstruct is loosely held in the tube, thereby removing the medicalconstruct and placing the medical construct in the body.
 2. A methodaccording to claim 1, wherein the medical construct comprises dry orpartially hydrated fibers when held inside the tube that swell whenhydrated in the body.
 3. A method according to claim 1, wherein themedical construct comprises a plurality of strands of biocompatiblecollagen fibers having at least a portion that is braided or twisted. 4.A method according to claim 1, further comprising inserting the needlein soft tissue before the pulling and compressing steps, wherein thepulling comprises pulling the needle and tube through the soft tissue,wherein the compressing is carried out so that the tube and the medicalconstruct are compressed in response to pressure applied from contactwith the soft tissue during the pulling step thereby also pulling theportion of the medical construct held in the tube through the softtissue; and wherein the separating step is carried out by continuing topull the tube after the tube has exited the soft tissue so that themedical construct is loosely held in the tube thereby placing themedical implant in the body.
 5. A method of assembling a medicaldelivery device with an implant for subsequent intrabody placementduring a medical procedure, comprising: providing a needle attached to acompressible tube having an open interior channel that extends adistance away from the needle; and slidably inserting a medical implantcomprising non-hydrated or partially hydrated braided and/or twistedcollagen fibers into the open interior channel of the tube so that theimplant is loosely held therein for intrabody placement using the needleand tube.
 6. A method according to claim 1, wherein the tube has an endportion that is fixedly attached to the needle, and wherein thecompressible tube has an elongate body which is flexible and impermeableand that increases in diameter relative to the end portion attached tothe needle, and wherein the compressible tube open interior channel hasan open trailing end opposing the needle, and wherein the separatingstep is carried out by pulling the needle and compressible tube out ofthe body of the subject while the elongate medical construct exits theopen trailing end to thereby place the medical implant in the body.
 7. Amethod according to claim 1, wherein the medical construct has a lengthwith a leading end and an opposing trailing end, wherein the leading endis held as a free end inside the tube spaced apart a distance from atrailing end of the needle, wherein the leading end is not directly orindirectly attached to the tube or any needle, and wherein between20-100% of the flexible medical construct length is held in the openelongate interior channel of the tube during the providing and pullingsteps.
 8. A method according to claim 1, wherein the elongate medicalconstruct is flexible and is releasably and loosely held inside the tubeduring the providing step, and wherein the separating step is carriedout by the medical construct slidably exiting an open trailing end ofthe tube when the medical construct is disposed within soft tissue ofthe local structure while the needle and the tube are pulled out of andaway from the soft tissue.
 9. A method according to claim 1, wherein thetube is configured so that during the compressing caused by contact withsoft tissue of the local structure during implantation temporarilycompresses the tube such that only this compression tightly holds theimplant therein.
 10. A method according to claim 1, wherein the medicalconstruct has a length held in the interior channel of the tube that isat least 3 cm and/or is at least 30% of the construct length, andwherein the providing step is carried out to slidably insert the medicalconstruct into the tube interior channel to be loosely held inside thetube interior channel.
 11. A method according to claim 1, wherein thetube has a forward end portion that resides in an interior chamber of arearward portion of the needle.
 12. A method according to claim 1,wherein the tube is swaged to the needle and has a smooth transitionsegment from the needle to the tube to inhibit snagging when insertedthrough soft tissue during surgical use.
 13. A method according to claim1, wherein the needle is shank-less and has a constant diameter outerwall upstream from a tip portion thereof, and wherein an inner wall of afirst segment of the tube is affixed to the outer wall of the needle,and wherein the medical construct is a flexible medical implant thatcomprises a dry or partially hydrated collagen fiber implant.
 14. Amethod according to claim 1, wherein the tube is heat-shrink tubing thatis heated to shrink to conform and affix to an outer wall of the needle,and wherein the compressible tube holds at least 40% of a length of themedical construct therein.
 15. A method according to claim 1, whereinthe medical construct in the interior channel of the tube is a length ofdry or partially hydrated biocompatible collagen fibers twisted, wovenor braided together that swell when exposed to a local fluidicenvironment in situ.
 16. A method according to claim 1, wherein themethod further comprises placing the medical construct in soft tissue ofthe body of the subject as a ligament repair device.
 17. A methodaccording to claim 1, wherein the method further comprises placing themedical construct in soft tissue of the body of the subject as a tendonrepair device.
 18. A method according to claim 1, wherein the methodfurther comprises placing the medical construct in soft tissue of thebody of the subject as at least one of a suture or a cable that isconfigured to repair an acromioclavicular (AC) joint.
 19. The method ofclaim 1, wherein the medical construct is a flexible medical implantthat, during the providing step, is held inside the tube interiorchannel so that the leading end is spaced apart from a trailing end ofthe needle to not contact the needle and wall of the tube encasing theinterior channel between the trailing end of the needle and the leadingend of the flexible implant.